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1.
We summarize recent statistical analyses that link agricultural yields to weather fluctuations. Similar to other sectors, high temperatures play a crucial role in predicting outcomes. Climate change is predicted to significantly increase high temperatures and thereby reduce yields. How good are such models at predicting future outcomes? We show that a statistical model estimated using historic US data on corn and soybean yields from 1950 to 2011 is very capable of predicting aggregate US yields for the years 2012–2015, where 2012 was much hotter than normal and is expected to become the new normal under climate change. We conclude by discussing recent studies on the implication of predicted yield declines with a special focus on adaptation and commodity prices. 相似文献
2.
Laurian J. Unnevehr 《Agricultural Economics》2007,37(S1):149-158
3.
Agriculture and forestry play an important role in emitting and storing greenhouse gases. For an efficient and cost-effective climate policy, it is therefore important to include land use, land-use change, and forestry (LULUCF) explicitly in economy-climate models. This article gives an overview and assessment of existing approaches to include LULUCF into partial and general equilibrium economy-climate models. For each class of models, we describe different examples, their treatment of land, and their potential for and applicability to policy analysis, as well as their shortcomings. We identify data requirements and conceptual problems, and provide suggestions for future research. 相似文献
4.
With the booming development of urban underground space in China, “fuzzy” property rights of this special form of land use type are not only the cause of ownership disputation and registration chaos, but also may seriously delay the undertaking of related underground land laws or regulations. China's emerging property rights issue of urban underground space, especially the delimitation of the surface and ground or underground, is facing such a challenge. This article aims to identify the property rights of urban underground space by using a practical method that classifies the underground space as economic goods, and to analyze attributes of different property rights of urban underground space within the theoretical framework of public goods. We use civil defense projects and underground parking lots as case studies. Both case studies are the most utilized types and controversial ownership cases of urban underground space in present China. Our case studies indicate that it is a feasible method to avoid the delimitation of the start-stop height of 3D property right vertically, and directly define the attributes of surface and underground property rights in line with the supply mode of goods. Our results show that the method proposed in this study can effectively solve the dispute of property rights against problems rising with unclear contract and lags in the legislation of urban underground space and clearly delimited the interests boundaries among different parties of property rights for urban underground space. Ultimately, this study may offer better insight into the utilization and registration work of urban underground space in China as well as reference for countries with similar property rights issues. 相似文献
5.
Likely climate change impacts include damages to agricultural production resulting from increased exposure to extreme heat. Considerable uncertainty remains regarding impacts on crop insurance programs. We utilize a panel of U.S. corn yield data to predict the effect of warming temperatures on the mean and variance of yields, as well as crop insurance premium rates and producer subsidies. While we focus on corn, we demonstrate that the subsidy impacts are likely to carry over to other major program crops. We find that warming decreases mean yields and increases yield risk on average, which results in higher premium rates. Under a 1°C warming scenario, we find that premium rates at the 90% coverage level will increase by 39% on average; however, there is considerable statistical uncertainty around this average as the 95% confidence interval spans from 22% to 61%. We also find evidence of extensive cross‐sectional differences as the county‐level rate impacts range from a 10% reduction to a 63% increase. Results indicate that exposure to extreme heat and changes in the coefficient of variation are large drivers of the impacts. Under the 1°C warming scenario, we find that annual subsidy payments for the crop insurance program could increase by as much as $1.5 billion, representing a 22% increase relative to current levels. This estimate increases to 3.7 billion (57%) under a 2°C warming scenario. Our results correspond to a very specific counterfactual: the marginal effect of warming temperatures under current technology, production, and crop insurance enrollments. These impacts are shown to be smaller than the forecasted impacts under a commonly used end‐of‐century general circulation model for even the most optimistic CO2 emissions projection. 相似文献
6.
Ecosystem-based adaptation (EbA) measures have been increasingly promoted in the literature, as well as in policies and practices, for their environmental and socio-economic co-benefits. The recent scientific literature has shown a growing interest to assess climate adaptation plans at the urban level, in recognition of the important role played by urban areas in addressing climate change challenges. However, little information is available on the combination of these two issues, i.e., the actual inclusion of EbA measures in climate adaptation plans at the urban level. This paper addresses this gap by developing a framework to analyze the treatment of EbA in urban level climate planning, and apply it to a sample of climate adaptation plans in Europe. The framework consists of a classification of EbA measures, and a scoring system to evaluate how well they are reflected in different components of the plans. The results suggest that there is in general good awareness in plans of EbA measures, and of their potential role in addressing climate change challenges. However, their treatment in climate adaptation plans at the urban level often lacks sufficient baseline information, as well as convincing implementation actions. The paper concludes by offering recommendations to improve future practice, in terms of enhancing the baseline information to improve the proposal and design of EbA measures, improving the treatment of co-benefits associated to EbA measures, and strengthening coordination with other planning tools. Possible future development of this works include the integration of the proposed EbA classification, and the analysis of a larger sample of territorial plans. 相似文献
7.
Consumption of natural resources should not exceed sustainable levels. The increasing use of biofuels and to some extent biomaterials, on top of rising food and feed demands, is causing countries to use a growing amount of global land, which may lead to land use conflicts and the expansion of cropland and intensive cultivation at the expense of natural ecosystems. Selective product certification cannot control the land use change triggered by growing overall biomass consumption. We propose a comprehensive approach to account for the global land use of countries for their domestic consumption, and assess this level with regard to globally acceptable levels of resource use, based on the concept of safe operating space. It is shown that the European Union currently uses one-third more cropland than globally available on a per capita basis and that with constant consumption levels it would exceed its fair share of acceptable resource use in 2030. As the use of global forests to meet renewable energy targets is becoming a concern, an approach to account for sustainable levels of timber flows is also proposed, based on the use of net annual increment, exemplified with preliminary data for Switzerland. Altogether, our approach would integrate the concept of sustainable consumption into national resource management plans; offering a conceptual basis and concrete reference values for informed policy making and urging countries to monitor and adjust their levels of resource consumption in a comprehensive way, respectful of the limits of sustainable supply. 相似文献
8.
Over the past century, U.S. farmers have been offered a steady stream of new agricultural technologies, and more recently, experienced climate change. Because these two events have been occurring simultaneously, identifying their separate effects is difficult, and misimputation is easy. This article explicitly examines the economics of technical change and the interaction between weather and technology as revealed in a half century of panel data on U.S. Midwest rainfed state‐average corn yields. Observed yields reflect two components: yield potential and damage to the potential caused by weather and pests. Yield potential is modeled as a stochastic production frontier where nitrogen fertilization, public corn research, and introduction and adoption of biotech corn seeds impact yield potential and excess heat impacts nitrogen productivity. The yield‐damage/damage‐control function permits biotech corn plants to abate adverse effects of weather and pest events. Results include the following: nitrogen use, public corn research, and biotech seed‐corn adoption increase yield potential; soil moisture stress reduces yield potential, and excess heat severely reduces nitrogen productivity. Biotech corn plants abate yield damage caused by soil moisture stress but not excess heat. 相似文献
9.
论矿物元素是地质与农业结合的切入点 总被引:9,自引:0,他引:9
应用农业地质对比种植的基本方法,对贵州的优质大米、烤烟和茶叶种植与地质环境关系进行研究,总结出优质农产品产量和品质与矿物元素在农产品中的含量成正比,证明矿物营养元素与产品质量有密切关系。而矿物元素来自地质体,本文以矿物元素为纽带,把岩石-土壤-农作物-农产品结合成一个整体,论述矿物元素是地质与农业结合的切入点。 相似文献
10.
Empirical studies point to reduced tillage as a means to increase yields and reverse land degradation. A relatively neglected avenue of research concerns why farmers increase tillage frequencies. Using household-plot level panel data from the Nile Basin of Ethiopia, this article applies a random effects ordered probit endogenous switching regression model to empirically investigate the impact of weather events and other conditioning factors on farmers’ choice of tillage intensity and the effect of changing tillage frequencies on differences in farm returns. Results indicate that, while low frequency tillage is more likely in drier areas, plot-level shocks (such as pests and diseases) are key variables in the choice of high-frequency tillage. Adoption of a low-till approach leads to increasing farm returns in low-moisture areas but high-frequency tillage provides higher returns in high-rainfall areas. Understanding how farmers’ tillage options correlate with climatic conditions and farm economies is salient for developing effective adaptation and mitigation plans. 相似文献
11.
This study attempts to investigate the potential to develop a regional framework of public participation (PP) in environmental assessments (EA) within Asia. In so-doing, this paper examines the status quo of public participation in EA within Asia from a legislative point of view. The existing situation of EA in Asia is first examined, followed by an analysis on the status and challenges of PP within the region’s environmental assessments. Eight Asian countries subject for this research have all implemented EA at different degrees, yet challenges of enforcement remain. Possible solutions to these challenges are to first improve and standardize the legal framework and implementation mechanism in each individual country, as a first step leading to a transboundary framework in Asia. PP within EA is legally defined in some countries, but it is not widely practiced. Multi-stakeholder process is suggested as a potential tool that comprehensively covers the components necessary for PP promotion. There are information gaps between countries, which could be improved by creating a regional agency governing information exchange. Limited collaboration among countries, likewise, could be improved by bilateral or multilateral environmental agreements. 相似文献
12.
Within only two decades olive oil developed from a niche product which could hardly be found in food stores outside the producing regions towards an integrated component in the diets of industrial countries. This paper discusses the impacts of the promotion of the “healthy Mediterranean diet” on land use and agro-ecosystems in the producing countries. It examines the dynamics of olive oil production, trade and consumption in the EU15 in the period 1972–2003 and the links between dietary patterns, trade and land use. It analyses the underlying socio-economic driving forces behind the increasing spatial disconnect between production and consumption of olive oil in the EU15 and in particular in Spain, the world largest producer during the last three decades. 相似文献
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14.
Putting climate change policy-integration into practice is challenged by problems of institutional misfit, due to, inter alia, deficient vertical administrative interplay. While most focus within the field of climate change research has targeted the national–local interplay, less is known about the interface of regional and local perspectives. Here, the aim is to study that interface with a specific focus on the relation between regional and local spatial planning actors, through a case-study of transport and coastal zone management in a Swedish municipality. The article is based on interviews (focus group and single in-depth) and official planning documents. The material reveals a tricky planning situation, replete with conflict. In practice, various institutional frameworks, claims and ambitions collide. The attempts to steer the local spatial planning initiatives from the regional level led to conflicts, which in turn seems to have hampered the overall work for climate change management through spatial planning. Furthermore, there are few traces of prospects of a smooth vertical institutional interplay able to support the overall aims related to integrating climate change mitigation and adaptation in spatial planning. 相似文献
15.
Christian Brannstrom Wendy Jepson Anthony M. Filippi Daniel Redo Zengwang Xu Srinivasan Ganesh 《Land use policy》2008,25(4):579-595
The Brazilian Cerrado, a biodiverse savanna ecoregion covering 1.8 million km2 south and east of the Amazon rainforest, is in rapid decline because of the expansion of modern agriculture. Previous studies of Cerrado land-use and land-cover (LULC) change imply spatial homogeneity, report widely varying rates of land conversion, use ambiguous LULC categories, and generally do not attempt to validate results. This study addresses this gap in the literature by analyzing moderate-resolution, multi-spectral satellite remote sensing data from 1986 to 2002 in two regions with identical underlying drivers. Unsupervised classification by the ISODATA algorithm indicates that Cerrado was converted to agro-pastoral land covers in 31% (3646 km2) of the study region in western Bahia and 24% (3011 km2) of the eastern Mato Grosso study region, while nearly 40% (4688 km2 and 5217 km2, respectively) of each study region remained unchanged. Although aggregate land change is similar, large and contiguous fragments persist in western Bahia, while smaller fragments remain in eastern Mato Grosso. These findings are considered in the current context of Cerrado land-use policy, which is dominated by the conservation set-aside and command-control policy models. The spatial characteristics of Cerrado remnants create considerable obstacles to implement the models; an alternative approach, informed by countryside biogeography, may encourage collaboration between state officials and farmer-landowners toward conservation land-use policies. 相似文献
16.
New institutional approach to collaborative forest planning on public land: Methods for analysis and lessons for policy 总被引:1,自引:0,他引:1
Kaisa Raitio 《Land use policy》2012,29(2):309-316
Collaborative planning has become an increasingly popular approach in environmental decision-making, particularly in situations where there are multiple actors with conflicting interests. In this paper, collaborative environmental planning is perceived as being embedded in an institutional environment that has an impact on the processes and outcomes of planning. Building on the theory of new institutionalism, the paper combines legal analysis of forest regulation with interviews and policy document data from two case studies on collaborative Natural Resource Planning in state-owned forests in Finland. These approaches will be used to analyse how formal regulations and informal norms are interpreted and implemented in the planning processes. The paper highlights the important role institutions can play in promoting or hindering successful collaborative planning, and makes recommendations for developing a forest governance system that is equipped to deal with the identified challenges. 相似文献
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18.
Temporal and spatial modelling of tropical deforestation: a survival analysis linking satellite and household survey data 总被引:5,自引:0,他引:5
We estimate a spatially explicit model of the forest clearance process among smallholder farmers in an agricultural frontier of southern Mexico. Our analysis takes as its point of departure a simple utility‐maximising model that suggests many possible determinants of deforestation in an economic environment characterised by missing or thin markets. Hypotheses from the model are tested on a data set that combines a time series of satellite imagery with data collected from a survey of farm households whose agricultural plots were geo‐referenced using a global positioning system (GPS). We implement a survival analysis to identify the effect of household level explanatory variables on the probability of deforestation. This approach allows us to introduce a measure of the time until clearance as a covariate, thereby affording a control for the effect of potentially important explanatory variables that vary through time but are not directly observable. In addition to identifying several variables relevant for policy analysis, including household demographics, proximity to roads, and government provision of agricultural support, model results suggest that the deforestation process is characterised by non‐linear duration dependence, with the probability of forest clearance first decreasing and then increasing with the passage of time. 相似文献
19.
Increasing water scarcity combined with an increasing demand for food and water for irrigation call for a careful revision of water use in agriculture. Currently, less than 60% of all the water used for irrigation is effectively used by crops. Based on the new version of the GTAP‐W model we analyze the effect of potential water savings and the welfare implications of improvements in irrigation efficiency worldwide. The results show that a water policy directed to improve irrigation efficiency led to global and regional water savings, but it is not beneficial for all regions. The final effect on regional welfare will depend on the interaction of several different causes. For instance, higher irrigation efficiency changes opportunity costs and reverses comparative advantages, modifying regional trade patterns and welfare. For water‐stressed regions the effects on welfare are mostly positive. For nonwater scarce regions the results are more mixed and mostly negative. The results show that exports of virtual water are not exclusive of water abundant regions. 相似文献
20.
Hermann Lotze‐Campen Christoph Müller Alberte Bondeau Stefanie Rost Alexander Popp Wolfgang Lucht 《Agricultural Economics》2008,39(3):325-338
In the coming decades, an increasing competition for global land and water resources can be expected, due to rising demand for food and bio‐energy production, biodiversity conservation, and changing production conditions due to climate change. The potential of technological change in agriculture to adapt to these trends is subject to considerable uncertainty. In order to simulate these combined effects in a spatially explicit way, we present a model of agricultural production and its impact on the environment (MAgPIE). MAgPIE is a mathematical programming model covering the most important agricultural crop and livestock production types in 10 economic regions worldwide at a spatial resolution of three by three degrees, i.e., approximately 300 by 300 km at the equator. It takes regional economic conditions as well as spatially explicit data on potential crop yields and land and water constraints into account and derives specific land‐use patterns for each grid cell. Shadow prices for binding constraints can be used to valuate resources for which in many places no markets exist, especially irrigation water. In this article, we describe the model structure and validation. We apply the model to possible future scenarios up to 2055 and derive required rates of technological change (i.e., yield increase) in agricultural production in order to meet future food demand. 相似文献